Combination lock



J. Ni. FERGUSON COMBINATION LOCK Nov. 2 9 1926. 1,604,983

Filed Dec. 20, 1924 Patented Non. 2, 1926s u i wat COMBINATION LOCK.

Application lecl `December 29,1924, Serial 'N-o. 757,219, and in Australia October 20, 1924.

This invention relates' to locks but more especially refers to thek style` of loclevvhch does not require a keyy for its operation, a type Which is generally referred to as acombination lock.

The object of the invention is to proyide a lock of this description' vvhich can be easily and cheaply manufactured and whichY will be eihcient and positive in itsoperation. The lock has been primarily devised forusev on motor carsl for securing various partsof the mechanism in order to prevent unauthorized use thereof butmay be applied Withequal facility for any other analogous purposes.

VThe device consists briefly ofa shafthav'- ing an interrupted key` therecin Working .in a casing through a series of rotatable `discs Which are-adapted to be brought into predetermined positions `by meanserterior to the casing to permit of free movementA ofthe shaft.

The lock Will now be described with reference to the accompanying drawings `in Whichri i Figure 1 is a perspective lvieu? of thecomplete lock, t

Figure 2 is a sectional perspective. vievv showing the internal arrangement thereof,

Figure 3 is a sectional elevation,

Figure 4 is an extended view showing the relationship between the various internal moving parts When the device is unlocked.

Figure 5 is a series of end elevations of these various parts.

Figure 6 is a similar vieW to Figure 4 with the device locked, and

Figure 7 is a View similar to Figure 5 of the parts shown in Figure 6.

rllhe device consists of a casing formed in tvvo parts 8 and 9 the front part 3 of Which is provided with a graduated cap 10, an internal shoulder 11 and an end cap 12. Between the shoulder 11V and the cap 12 are a series of rotatable discs 13, 14, and 15 and distance pieces 16, 17, and 18. The bar 19 passes through the cap 10, the discs 13, 14, and 15 and end cap 12. The rear part of the casing 9 screws onto the front part 8 and is provided With a central boss 2O which receives a tube 21 through which in this eX- ample a Wire 22 attached to the mechanism to be operated and to the shaft 19, passes.

The graduated cap is marked with a series of numbers and is provided With indentations 23 and adapted to engage with the pointer 24attached to the casing 8. The bar has a knob 25 and a raised ley 26 thereon, said key being cut away at 27, 28, and 29, the spaces equal to the thickness of the discs 13,14, and 15. The end'cap 12 has a lzeyvvay so placed'thereinias to allovv the shaft 19 to'pass therethrough. The discs 13, 14, and 15; alsoy have keyvvays31 therein While the disc`13 has a comparatively long circular slot 32, the disc 14 has a relatively shorter slot'33. The cap 1Q and disc 15 are united rigidly by the rod 34frvhich passes through thev slots 32 and 33.

rihe,"operation `vvill now be described. Normally when locked thef'bar 19 is Withdrawn so that the breaks .27," 28', and 29 in the` key 2,6 correspond yviththe discs 13, 14, and 15 which are arranged'in any position' to lock the shaft asv shown in Figures' 6 'andi 7. When it is desired to unlock the `device the cap isrotated toa predetermined yposition thereby rotating the4 discs 13, 14, and 15 until thekeyyvayfin disc 13 comes opposite the key 26. VThe cap 10 is then Vrotated `in the opposite direction taking with it the discs 14 and 15 and leaving the disc 13 stationary because the `rod 34 passesfreely through the slovtf32, until the lheyy?ay in `disc 14fis brought tated in the opposite direction again, until the keyway in disc is lbrought into alignment With key 26, the disc 14 remaining sta` tionary as the rod 34 passes freely along 33. The bar 19 may then be operated, the discs being in the position shown in Figures 4 and 5 all the lreyvvays being in alignment.

The amount of turning of the cap 10 as Well as the initial direction is governed by the position of the keyvvays 31 relative to the slots 32 and the rod 34. This is arranged in the assembling of each device so that a certain combination is required to release the shaft 19.

For example, suppose the required positions of the various discs correspond to the numbers 2,7 7, and O on the cap 10 and that the cap has to be turned initially to the right, the first movement is to turn the cap 10 to the right until the indentation 23 corresponding to the numeral 2 isv brought into engagement with pointer 24. This brings the disc 13 to its proper posit-ion. The next movement is to rotate the cap 19 to the left until the indentation corresponding to 7 engages 24. rlhis brings disc 14- to its correct position. The last movement is the turning of the cap 10 to the right again so that O is brought opposite pointer 2Lithus bringing disc 15 to its proper position for releasing the bar 19. The knob may then be depressed. XVhen it is desired to lock the device the knob and bar 19 are withdrawn and the cap 10 given a few random turns thus upsetting the combination.

The slots 32 and 33 are not coniined to the exact length shown but may extend practically round the whole disc and by altering the positions o1 keyways 31 in the discs 13, 14, and 15 relative to the positions of the slots 3Q, 33, and 34e a new set of stopping places Jrior the cap 10 are required which may be, for example, 7, O, 2 with the initial movement to the left.

The keyway in the cap 12 maintains the bar 19 in a constant position and the spring 35 acts as a brake to steady it.

The device has been described with three discs but it is obvious that it may if desired include two or four or more. Other minor variations may be made in the arrangement and construction of the parts without departing from the principle of the invention.

I claim 1. A locking device comprising a casing, a rotatable cap at one end ot said casing, a series of spaced coaxially aligned rotatable discs within said casing, each of said discs being provided with a lreyway, a bar adapted to pass through the centers of said rotatable cap and said discs, and a rigid rod connecting said cap and the rearrnost disc, each of the other discs being provided with a segmental slot through which said connectingv rod passes, whereby upon rotation of said cap the lreyways in said discs may be aligned to permit longitudinal movement of said bar.

2. A locking device comprising a casing, a fixed rear end cap, a series of discs rotatable between distance pieces within said casing, keyways and slots in said discs, and a centrally situated bar passing through said discs and said end cap and having an interrupted key thereon, a rotatable front cap surrounding said bar, a rigid connection bar between said rotatable front cap and the rearmost of said rotatable discs, said bar passing through said slots in said intervening discs and means for indicating the positionpoi' said rotatable front cap.

8. A locking device comprising a 'front casing a rear casing, a front rotatable cap, a fixed cap at rear end of said iront casing7 a series of discs rotatable between distance pieces in said front casing, lreyw( ys in said discs and said iiXed cap, slots in said discs, a centrally situated bar passing through said rotatable front cap said discs and said rear cap, a key formed on said bar, interruptions in said key, a rigid bar connecting said rotatable cap and the rearmost of said rotatable discs, said bar passing through said slots in said intervening rotatable discs, graduations on said rotatable cap and means for indica*- ing the position ot said graduations and means tor attaching said bar to the mechanism to be operated and for passing said mechanism through said rear casing.

In testimony whereof -I have affixed my signature.

JOHN MALCOLM FERGUSON. 

